Conventionally, a shopping cart is designed to be nestable into a preceding, similarly constructed cart and to enable a following, similarly constructed cart to be nested into the shopping cart. Commonly, in retail stores and in parking areas near retail stores, long lines of nested shopping carts may be formed, which must be moved by store personnel.
Typically, a rear caster comprises a horn, which unlike the horn of a front caster does not swivel and which mounts an axle, and a wheel, which is journalled on the axle, via a bearing, and which has a tread. Moving of a line of nested shopping carts stresses rear casters of the nested carts, tends to cause the horns of said casters to bend, and tends to cause the bearings and treads of said casters to wear excessively, particularly as attempts are made to turn the line of nested shopping carts.